Capacity in healthcare decision-making refers to a patient’s functional ability to make an informed choice about their medical care. This ability is foundational to informed consent, which is the patient’s right to accept or refuse treatment. Capacity is always decision-specific; a person might have the capacity to choose a simple medication but not a complex surgical procedure. It is also dynamic and can fluctuate depending on a patient’s condition or the medical environment. Healthcare providers presume all adult patients have capacity until an assessment suggests otherwise, usually triggered by a decision that seems irrational or against their self-interest.
The Elements of Capacity Assessment
Healthcare providers determine a patient’s capacity by assessing four distinct cognitive elements, a process that is clinical rather than legal.
Understanding
This requires the patient to comprehend the relevant medical information provided by the clinician. This includes understanding the nature of their condition, the proposed treatment, and the potential risks and benefits associated with the treatment and the alternative of no treatment.
Appreciation
The patient must recognize how the information applies directly to their own situation and health status. A patient may intellectually understand the risks of a procedure but fail to appreciate that those risks apply to them personally. The patient must internalize the potential consequences for themselves, not just repeat the facts back to the provider.
Reasoning
This involves the patient’s ability to manipulate the information logically to reach a decision. This includes weighing the treatment options, comparing the risks and benefits, and demonstrating a rational process. The patient’s ultimate choice does not need to align with the medical recommendation, but the thought process must be coherent and based on their values.
Express a Choice
The patient must be able to communicate their decision clearly and consistently to the healthcare team. The decision must remain stable long enough for the plan to be implemented. A deficit in any single one of these four elements is sufficient grounds to determine that the patient lacks capacity for that particular decision.
The Difference Between Capacity and Competence
While the terms are often used interchangeably, capacity and competence have distinct meanings in the medical and legal fields. Capacity is a clinical determination made by a healthcare provider at the bedside. This assessment is functional and relates only to the patient’s ability to make a specific medical decision at a particular moment in time.
Competence, in contrast, is a legal determination that can only be made by a judge or court of law. A finding of incompetence is a global assessment that removes a person’s legal right to manage their own affairs, including financial matters and all healthcare decisions. The legal process is formal, enduring, and applies to all decisions, unlike a clinician’s finding of incapacity, which is temporary and limited.
In medical practice, all adults are presumed to be legally competent unless a clinical assessment determines otherwise. The clinical finding of incapacity may be challenged, escalating the situation to the legal system for a formal determination of incompetence. However, most daily medical decisions rely solely on the clinician’s capacity assessment, which is a faster tool for protecting patient autonomy and well-being.
Factors That Temporarily Affect Capacity
Capacity is not a fixed trait and can fluctuate significantly due to temporary medical and environmental factors. One common cause of temporary impairment is delirium, an acute change in mental status often triggered by infection, fever, or metabolic imbalances. A patient experiencing delirium may be too confused or disorganized to understand the information presented.
Severe physical conditions, such as uncontrolled pain, can overwhelm a patient’s ability to focus and engage in rational thought. Medications, particularly heavy sedatives, anesthesia, or strong opioid pain relievers, can also temporarily impair cognitive function. Capacity must be reassessed once the underlying cause, such as the infection or the drug’s peak effect, has resolved or improved.
Acute psychiatric crises, including severe depression or active psychosis, can interfere with a patient’s ability to appreciate their situation realistically. A patient may understand the information but hold a delusional belief that prevents them from applying it to their own health. Because these factors are transient, healthcare teams often delay non-urgent decisions until the patient’s mental clarity is maximized.
How Decisions Are Made When Capacity Is Absent
When a patient lacks capacity for a specific medical decision, the healthcare team must turn to a surrogate decision-maker. The first step is to look for the patient’s previously expressed wishes, formalized in an Advance Directive. This legal document may be a Living Will, outlining specific treatment preferences, or a Durable Power of Attorney for Healthcare, naming a specific healthcare agent.
If no formal directive exists, a hierarchy of family members, established by state law, is consulted to find the default surrogate. This hierarchy usually prioritizes:
- The spouse.
- Adult children.
- Parents.
- Adult siblings.
If a court has previously found the patient legally incompetent, a court-appointed guardian or conservator will have the authority to make decisions.
The surrogate is legally and ethically bound to follow two primary standards. The first is substituted judgment, requiring the surrogate to choose the option the patient would have chosen if able to decide, relying on knowledge of the patient’s values and past statements. If the patient’s wishes are entirely unknown, the surrogate must use the best interest standard, choosing the option that is medically appropriate and maximizes the patient’s overall well-being.